Document Detail


Stable isotope (N, C, Hg) study of methylmercury sources and trophic transfer in the northern gulf of Mexico.
MedLine Citation:
PMID:  20104887     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We combined N, C, and Hg stable isotope measurements to identify the most important factors that influence MeHg accumulation in fish from the northern Gulf of Mexico (nGOM), and to determine if coastal species residing in the Mississippi River (MR) plume and migratory oceanic species derive their MeHg from the same, or different, sources. In six coastal species and two oceanic species (blackfin and yellowfin tuna), trophic position as measured by delta(15)N explained most of the variance in log[MeHg] (r(2) approximately 0.8), but coastal species and tuna fell along distinct, nearly parallel lines with significantly different intercepts. The tuna also had significantly higher delta(202)Hg (0.2-0.5 per thousand) and Delta(201)Hg ( approximately 1.5 per thousand) than the coastal fish (delta(202)Hg = 0 to -1.0 per thousand; Delta(201)Hg approximately 0.4 per thousand). The observations can be best explained by largely disconnected food webs rooted in different baseline delta(15)N signatures (MR-plume vs oceanic) and isotopically distinct MeHg sources, with oceanic MeHg having undergone substantial photodegradation ( approximately 50%) before entering the base of the food web. Given the MR's large, productive footprint in the nGOM and the potential for exporting prey and MeHg to the adjacent oligotrophic GOM, the disconnected food webs and different MeHg sources are consistent with recent evidence in other systems of important oceanic MeHg sources.
Authors:
David B Senn; Edward J Chesney; Joel D Blum; Michael S Bank; Amund Maage; James P Shine
Related Documents :
17909967 - Adverse effects from environmental mercury loads on breeding common loons.
9273927 - Organic mercury: an environmental threat to the health of dietary-exposed societies?
11357867 - The effects of experimental reservoir creation on the bioaccumulation of methylmercury ...
20407747 - Assessment of total mercury level in fish collected from east calcutta wetlands and tit...
22314907 - Effect of increased dietary calcium on body weight, food and water intake in oral contr...
21675807 - Optimal nutritional intake for fetal growth.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Environmental science & technology     Volume:  44     ISSN:  0013-936X     ISO Abbreviation:  Environ. Sci. Technol.     Publication Date:  2010 Mar 
Date Detail:
Created Date:  2010-02-25     Completed Date:  2010-04-29     Revised Date:  2014-04-08    
Medline Journal Info:
Nlm Unique ID:  0213155     Medline TA:  Environ Sci Technol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1630-7     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Carbon Isotopes / analysis*,  metabolism
Ecosystem
Environmental Monitoring / methods
Fishes / metabolism
Mercury Isotopes / analysis*,  metabolism
Methylmercury Compounds / analysis,  metabolism
Mexico
Nitrogen Isotopes / analysis*,  metabolism
Seasons
Seawater / analysis*
United States
Water Pollutants, Chemical / analysis
Chemical
Reg. No./Substance:
0/Carbon Isotopes; 0/Mercury Isotopes; 0/Methylmercury Compounds; 0/Nitrogen Isotopes; 0/Water Pollutants, Chemical

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Mechanisms and Specific Directionality of Autotrophic Nitrous Oxide and Nitric Oxide Generation duri...
Next Document:  Isolation of Ugi Four-Component Condensation Primary Adducts: A Straightforward Route to Isocoumarin...